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minix/lib/libc/nameser/ns_name.c
Ben Gras 2fe8fb192f Full switch to clang/ELF. Drop ack. Simplify. 
There is important information about booting non-ack images in
docs/UPDATING. ack/aout-format images can't be built any more, and
booting clang/ELF-format ones is a little different. Updating to the
new boot monitor is recommended.

Changes in this commit:

	. drop boot monitor -> allowing dropping ack support
	. facility to copy ELF boot files to /boot so that old boot monitor
	  can still boot fairly easily, see UPDATING
	. no more ack-format libraries -> single-case libraries
	. some cleanup of OBJECT_FMT, COMPILER_TYPE, etc cases
	. drop several ack toolchain commands, but not all support
	  commands (e.g. aal is gone but acksize is not yet).
	. a few libc files moved to netbsd libc dir
	. new /bin/date as minix date used code in libc/
	. test compile fix
	. harmonize includes
	. /usr/lib is no longer special: without ack, /usr/lib plays no
	  kind of special bootstrapping role any more and bootstrapping
	  is done exclusively through packages, so releases depend even
	  less on the state of the machine making them now.
	. rename nbsd_lib* to lib*
	. reduce mtree
2012-02-14 14:52:02 +01:00

1161 lines
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/* $NetBSD: ns_name.c,v 1.8 2009/04/12 19:43:37 christos Exp $ */
/*
* Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
* Copyright (c) 1996,1999 by Internet Software Consortium.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
* OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <sys/cdefs.h>
#ifndef lint
#ifdef notdef
static const char rcsid[] = "Id: ns_name.c,v 1.11 2009/01/23 19:59:16 each Exp";
#else
__RCSID("$NetBSD: ns_name.c,v 1.8 2009/04/12 19:43:37 christos Exp $");
#endif
#endif
#include "port_before.h"
#include <sys/types.h>
#include <netinet/in.h>
#include <arpa/nameser.h>
#include <errno.h>
#include <resolv.h>
#include <string.h>
#include <ctype.h>
#include <stdlib.h>
#include <limits.h>
#include "port_after.h"
#ifdef SPRINTF_CHAR
# define SPRINTF(x) strlen(sprintf/**/x)
#else
# define SPRINTF(x) ((size_t)sprintf x)
#endif
#define NS_TYPE_ELT 0x40 /*%< EDNS0 extended label type */
#define DNS_LABELTYPE_BITSTRING 0x41
/* Data. */
static const char digits[] = "0123456789";
static const char digitvalue[256] = {
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*16*/
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*32*/
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*48*/
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, -1, -1, -1, -1, -1, -1, /*64*/
-1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*80*/
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*96*/
-1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*112*/
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*128*/
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*256*/
};
/* Forward. */
static int special(int);
static int printable(int);
static int dn_find(const u_char *, const u_char *,
const u_char * const *,
const u_char * const *);
static int encode_bitsring(const char **, const char *,
unsigned char **, unsigned char **,
unsigned const char *);
static int labellen(const u_char *);
static int decode_bitstring(const unsigned char **,
char *, const char *);
/* Public. */
/*%
* Convert an encoded domain name to printable ascii as per RFC1035.
* return:
*\li Number of bytes written to buffer, or -1 (with errno set)
*
* notes:
*\li The root is returned as "."
*\li All other domains are returned in non absolute form
*/
int
ns_name_ntop(const u_char *src, char *dst, size_t dstsiz)
{
const u_char *cp;
char *dn, *eom;
u_char c;
u_int n;
int l;
cp = src;
dn = dst;
eom = dst + dstsiz;
while ((n = *cp++) != 0) {
if ((n & NS_CMPRSFLGS) == NS_CMPRSFLGS) {
/* Some kind of compression pointer. */
errno = EMSGSIZE;
return (-1);
}
if (dn != dst) {
if (dn >= eom) {
errno = EMSGSIZE;
return (-1);
}
*dn++ = '.';
}
if ((l = labellen(cp - 1)) < 0) {
errno = EMSGSIZE; /*%< XXX */
return (-1);
}
if (dn + l >= eom) {
errno = EMSGSIZE;
return (-1);
}
if ((n & NS_CMPRSFLGS) == NS_TYPE_ELT) {
int m;
if (n != DNS_LABELTYPE_BITSTRING) {
/* XXX: labellen should reject this case */
errno = EINVAL;
return (-1);
}
if ((m = decode_bitstring(&cp, dn, eom)) < 0)
{
errno = EMSGSIZE;
return (-1);
}
dn += m;
continue;
}
for (; l > 0; l--) {
c = *cp++;
if (special(c)) {
if (dn + 1 >= eom) {
errno = EMSGSIZE;
return (-1);
}
*dn++ = '\\';
*dn++ = (char)c;
} else if (!printable(c)) {
if (dn + 3 >= eom) {
errno = EMSGSIZE;
return (-1);
}
*dn++ = '\\';
*dn++ = digits[c / 100];
*dn++ = digits[(c % 100) / 10];
*dn++ = digits[c % 10];
} else {
if (dn >= eom) {
errno = EMSGSIZE;
return (-1);
}
*dn++ = (char)c;
}
}
}
if (dn == dst) {
if (dn >= eom) {
errno = EMSGSIZE;
return (-1);
}
*dn++ = '.';
}
if (dn >= eom) {
errno = EMSGSIZE;
return (-1);
}
*dn++ = '\0';
return (dn - dst);
}
/*%
* Convert a ascii string into an encoded domain name as per RFC1035.
*
* return:
*
*\li -1 if it fails
*\li 1 if string was fully qualified
*\li 0 is string was not fully qualified
*
* notes:
*\li Enforces label and domain length limits.
*/
int
ns_name_pton(const char *src, u_char *dst, size_t dstsiz) {
return (ns_name_pton2(src, dst, dstsiz, NULL));
}
/*
* ns_name_pton2(src, dst, dstsiz, *dstlen)
* Convert a ascii string into an encoded domain name as per RFC1035.
* return:
* -1 if it fails
* 1 if string was fully qualified
* 0 is string was not fully qualified
* side effects:
* fills in *dstlen (if non-NULL)
* notes:
* Enforces label and domain length limits.
*/
int
ns_name_pton2(const char *src, u_char *dst, size_t dstsiz, size_t *dstlen) {
u_char *label, *bp, *eom;
int c, n, escaped, e = 0;
char *cp;
escaped = 0;
bp = dst;
eom = dst + dstsiz;
label = bp++;
while ((c = *src++) != 0) {
if (escaped) {
if (c == '[') { /*%< start a bit string label */
if ((cp = strchr(src, ']')) == NULL) {
errno = EINVAL; /*%< ??? */
return (-1);
}
if ((e = encode_bitsring(&src, cp + 2,
&label, &bp, eom))
!= 0) {
errno = e;
return (-1);
}
escaped = 0;
label = bp++;
if ((c = *src++) == 0)
goto done;
else if (c != '.') {
errno = EINVAL;
return (-1);
}
continue;
}
else if ((cp = strchr(digits, c)) != NULL) {
n = (cp - digits) * 100;
if ((c = *src++) == 0 ||
(cp = strchr(digits, c)) == NULL) {
errno = EMSGSIZE;
return (-1);
}
n += (cp - digits) * 10;
if ((c = *src++) == 0 ||
(cp = strchr(digits, c)) == NULL) {
errno = EMSGSIZE;
return (-1);
}
n += (cp - digits);
if (n > 255) {
errno = EMSGSIZE;
return (-1);
}
c = n;
}
escaped = 0;
} else if (c == '\\') {
escaped = 1;
continue;
} else if (c == '.') {
c = (bp - label - 1);
if ((c & NS_CMPRSFLGS) != 0) { /*%< Label too big. */
errno = EMSGSIZE;
return (-1);
}
if (label >= eom) {
errno = EMSGSIZE;
return (-1);
}
*label = c;
/* Fully qualified ? */
if (*src == '\0') {
if (c != 0) {
if (bp >= eom) {
errno = EMSGSIZE;
return (-1);
}
*bp++ = '\0';
}
if ((bp - dst) > MAXCDNAME) {
errno = EMSGSIZE;
return (-1);
}
if (dstlen != NULL)
*dstlen = (bp - dst);
return (1);
}
if (c == 0 || *src == '.') {
errno = EMSGSIZE;
return (-1);
}
label = bp++;
continue;
}
if (bp >= eom) {
errno = EMSGSIZE;
return (-1);
}
*bp++ = (u_char)c;
}
c = (bp - label - 1);
if ((c & NS_CMPRSFLGS) != 0) { /*%< Label too big. */
errno = EMSGSIZE;
return (-1);
}
done:
if (label >= eom) {
errno = EMSGSIZE;
return (-1);
}
*label = c;
if (c != 0) {
if (bp >= eom) {
errno = EMSGSIZE;
return (-1);
}
*bp++ = 0;
}
if ((bp - dst) > MAXCDNAME) { /*%< src too big */
errno = EMSGSIZE;
return (-1);
}
if (dstlen != NULL)
*dstlen = (bp - dst);
return (0);
}
/*%
* Convert a network strings labels into all lowercase.
*
* return:
*\li Number of bytes written to buffer, or -1 (with errno set)
*
* notes:
*\li Enforces label and domain length limits.
*/
int
ns_name_ntol(const u_char *src, u_char *dst, size_t dstsiz)
{
const u_char *cp;
u_char *dn, *eom;
u_char c;
u_int n;
int l;
cp = src;
dn = dst;
eom = dst + dstsiz;
if (dn >= eom) {
errno = EMSGSIZE;
return (-1);
}
while ((n = *cp++) != 0) {
if ((n & NS_CMPRSFLGS) == NS_CMPRSFLGS) {
/* Some kind of compression pointer. */
errno = EMSGSIZE;
return (-1);
}
*dn++ = n;
if ((l = labellen(cp - 1)) < 0) {
errno = EMSGSIZE;
return (-1);
}
if (dn + l >= eom) {
errno = EMSGSIZE;
return (-1);
}
for (; l > 0; l--) {
c = *cp++;
if (isascii(c) && isupper(c))
*dn++ = tolower(c);
else
*dn++ = c;
}
}
*dn++ = '\0';
return (dn - dst);
}
/*%
* Unpack a domain name from a message, source may be compressed.
*
* return:
*\li -1 if it fails, or consumed octets if it succeeds.
*/
int
ns_name_unpack(const u_char *msg, const u_char *eom, const u_char *src,
u_char *dst, size_t dstsiz)
{
return (ns_name_unpack2(msg, eom, src, dst, dstsiz, NULL));
}
/*
* ns_name_unpack2(msg, eom, src, dst, dstsiz, *dstlen)
* Unpack a domain name from a message, source may be compressed.
* return:
* -1 if it fails, or consumed octets if it succeeds.
* side effect:
* fills in *dstlen (if non-NULL).
*/
int
ns_name_unpack2(const u_char *msg, const u_char *eom, const u_char *src,
u_char *dst, size_t dstsiz, size_t *dstlen)
{
const u_char *srcp, *dstlim;
u_char *dstp;
int n, len, checked, l;
len = -1;
checked = 0;
dstp = dst;
srcp = src;
dstlim = dst + dstsiz;
if (srcp < msg || srcp >= eom) {
errno = EMSGSIZE;
return (-1);
}
/* Fetch next label in domain name. */
while ((n = *srcp++) != 0) {
/* Check for indirection. */
switch (n & NS_CMPRSFLGS) {
case 0:
case NS_TYPE_ELT:
/* Limit checks. */
if ((l = labellen(srcp - 1)) < 0) {
errno = EMSGSIZE;
return (-1);
}
if (dstp + l + 1 >= dstlim || srcp + l >= eom) {
errno = EMSGSIZE;
return (-1);
}
checked += l + 1;
*dstp++ = n;
memcpy(dstp, srcp, (size_t)l);
dstp += l;
srcp += l;
break;
case NS_CMPRSFLGS:
if (srcp >= eom) {
errno = EMSGSIZE;
return (-1);
}
if (len < 0)
len = srcp - src + 1;
srcp = msg + (((n & 0x3f) << 8) | (*srcp & 0xff));
if (srcp < msg || srcp >= eom) { /*%< Out of range. */
errno = EMSGSIZE;
return (-1);
}
checked += 2;
/*
* Check for loops in the compressed name;
* if we've looked at the whole message,
* there must be a loop.
*/
if (checked >= eom - msg) {
errno = EMSGSIZE;
return (-1);
}
break;
default:
errno = EMSGSIZE;
return (-1); /*%< flag error */
}
}
*dstp++ = 0;
if (dstlen != NULL)
*dstlen = dstp - dst;
if (len < 0)
len = srcp - src;
return (len);
}
/*%
* Pack domain name 'domain' into 'comp_dn'.
*
* return:
*\li Size of the compressed name, or -1.
*
* notes:
*\li 'dnptrs' is an array of pointers to previous compressed names.
*\li dnptrs[0] is a pointer to the beginning of the message. The array
* ends with NULL.
*\li 'lastdnptr' is a pointer to the end of the array pointed to
* by 'dnptrs'.
*
* Side effects:
*\li The list of pointers in dnptrs is updated for labels inserted into
* the message as we compress the name. If 'dnptr' is NULL, we don't
* try to compress names. If 'lastdnptr' is NULL, we don't update the
* list.
*/
int
ns_name_pack(const u_char *src, u_char *dst, int dstsiz,
const u_char **dnptrs, const u_char **lastdnptr)
{
u_char *dstp;
const u_char **cpp, **lpp, *eob, *msg;
const u_char *srcp;
int n, l, first = 1;
srcp = src;
dstp = dst;
eob = dstp + dstsiz;
lpp = cpp = NULL;
if (dnptrs != NULL) {
if ((msg = *dnptrs++) != NULL) {
for (cpp = dnptrs; *cpp != NULL; cpp++)
continue;
lpp = cpp; /*%< end of list to search */
}
} else
msg = NULL;
/* make sure the domain we are about to add is legal */
l = 0;
do {
int l0;
n = *srcp;
if ((n & NS_CMPRSFLGS) == NS_CMPRSFLGS) {
errno = EMSGSIZE;
return (-1);
}
if ((l0 = labellen(srcp)) < 0) {
errno = EINVAL;
return (-1);
}
l += l0 + 1;
if (l > MAXCDNAME) {
errno = EMSGSIZE;
return (-1);
}
srcp += l0 + 1;
} while (n != 0);
/* from here on we need to reset compression pointer array on error */
srcp = src;
do {
/* Look to see if we can use pointers. */
n = *srcp;
if (n != 0 && msg != NULL) {
l = dn_find(srcp, msg, (const u_char * const *)dnptrs,
(const u_char * const *)lpp);
if (l >= 0) {
if (dstp + 1 >= eob) {
goto cleanup;
}
*dstp++ = ((u_int32_t)l >> 8) | NS_CMPRSFLGS;
*dstp++ = l % 256;
return (dstp - dst);
}
/* Not found, save it. */
if (lastdnptr != NULL && cpp < lastdnptr - 1 &&
(dstp - msg) < 0x4000 && first) {
*cpp++ = dstp;
*cpp = NULL;
first = 0;
}
}
/* copy label to buffer */
if ((n & NS_CMPRSFLGS) == NS_CMPRSFLGS) {
/* Should not happen. */
goto cleanup;
}
n = labellen(srcp);
if (dstp + 1 + n >= eob) {
goto cleanup;
}
memcpy(dstp, srcp, (size_t)(n + 1));
srcp += n + 1;
dstp += n + 1;
} while (n != 0);
if (dstp > eob) {
cleanup:
if (msg != NULL)
*lpp = NULL;
errno = EMSGSIZE;
return (-1);
}
return (dstp - dst);
}
/*%
* Expand compressed domain name to presentation format.
*
* return:
*\li Number of bytes read out of `src', or -1 (with errno set).
*
* note:
*\li Root domain returns as "." not "".
*/
int
ns_name_uncompress(const u_char *msg, const u_char *eom, const u_char *src,
char *dst, size_t dstsiz)
{
u_char tmp[NS_MAXCDNAME];
int n;
if ((n = ns_name_unpack(msg, eom, src, tmp, sizeof tmp)) == -1)
return (-1);
if (ns_name_ntop(tmp, dst, dstsiz) == -1)
return (-1);
return (n);
}
/*%
* Compress a domain name into wire format, using compression pointers.
*
* return:
*\li Number of bytes consumed in `dst' or -1 (with errno set).
*
* notes:
*\li 'dnptrs' is an array of pointers to previous compressed names.
*\li dnptrs[0] is a pointer to the beginning of the message.
*\li The list ends with NULL. 'lastdnptr' is a pointer to the end of the
* array pointed to by 'dnptrs'. Side effect is to update the list of
* pointers for labels inserted into the message as we compress the name.
*\li If 'dnptr' is NULL, we don't try to compress names. If 'lastdnptr'
* is NULL, we don't update the list.
*/
int
ns_name_compress(const char *src, u_char *dst, size_t dstsiz,
const u_char **dnptrs, const u_char **lastdnptr)
{
u_char tmp[NS_MAXCDNAME];
if (ns_name_pton(src, tmp, sizeof tmp) == -1)
return (-1);
return (ns_name_pack(tmp, dst, (int)dstsiz, dnptrs, lastdnptr));
}
/*%
* Reset dnptrs so that there are no active references to pointers at or
* after src.
*/
void
ns_name_rollback(const u_char *src, const u_char **dnptrs,
const u_char **lastdnptr)
{
while (dnptrs < lastdnptr && *dnptrs != NULL) {
if (*dnptrs >= src) {
*dnptrs = NULL;
break;
}
dnptrs++;
}
}
/*%
* Advance *ptrptr to skip over the compressed name it points at.
*
* return:
*\li 0 on success, -1 (with errno set) on failure.
*/
int
ns_name_skip(const u_char **ptrptr, const u_char *eom)
{
const u_char *cp;
u_int n;
int l;
cp = *ptrptr;
while (cp < eom && (n = *cp++) != 0) {
/* Check for indirection. */
switch (n & NS_CMPRSFLGS) {
case 0: /*%< normal case, n == len */
cp += n;
continue;
case NS_TYPE_ELT: /*%< EDNS0 extended label */
if ((l = labellen(cp - 1)) < 0) {
errno = EMSGSIZE; /*%< XXX */
return (-1);
}
cp += l;
continue;
case NS_CMPRSFLGS: /*%< indirection */
cp++;
break;
default: /*%< illegal type */
errno = EMSGSIZE;
return (-1);
}
break;
}
if (cp > eom) {
errno = EMSGSIZE;
return (-1);
}
*ptrptr = cp;
return (0);
}
/* Find the number of octets an nname takes up, including the root label.
* (This is basically ns_name_skip() without compression-pointer support.)
* ((NOTE: can only return zero if passed-in namesiz argument is zero.))
*/
ssize_t
ns_name_length(ns_nname_ct nname, size_t namesiz) {
ns_nname_ct orig = nname;
u_int n;
while (namesiz-- > 0 && (n = *nname++) != 0) {
if ((n & NS_CMPRSFLGS) != 0) {
errno = EISDIR;
return (-1);
}
if (n > namesiz) {
errno = EMSGSIZE;
return (-1);
}
nname += n;
namesiz -= n;
}
return (nname - orig);
}
/* Compare two nname's for equality. Return -1 on error (setting errno).
*/
int
ns_name_eq(ns_nname_ct a, size_t as, ns_nname_ct b, size_t bs) {
ns_nname_ct ae = a + as, be = b + bs;
int ac, bc;
while (ac = *a, bc = *b, ac != 0 && bc != 0) {
if ((ac & NS_CMPRSFLGS) != 0 || (bc & NS_CMPRSFLGS) != 0) {
errno = EISDIR;
return (-1);
}
if (a + ac >= ae || b + bc >= be) {
errno = EMSGSIZE;
return (-1);
}
if (ac != bc || strncasecmp((const char *) ++a,
(const char *) ++b,
(size_t)ac) != 0)
return (0);
a += ac, b += bc;
}
return (ac == 0 && bc == 0);
}
/* Is domain "A" owned by (at or below) domain "B"?
*/
int
ns_name_owned(ns_namemap_ct a, int an, ns_namemap_ct b, int bn) {
/* If A is shorter, it cannot be owned by B. */
if (an < bn)
return (0);
/* If they are unequal before the length of the shorter, A cannot... */
while (bn > 0) {
if (a->len != b->len ||
strncasecmp((const char *) a->base,
(const char *) b->base, (size_t)a->len) != 0)
return (0);
a++, an--;
b++, bn--;
}
/* A might be longer or not, but either way, B owns it. */
return (1);
}
/* Build an array of <base,len> tuples from an nname, top-down order.
* Return the number of tuples (labels) thus discovered.
*/
int
ns_name_map(ns_nname_ct nname, size_t namelen, ns_namemap_t map, int mapsize) {
u_int n;
int l;
n = *nname++;
namelen--;
/* Root zone? */
if (n == 0) {
/* Extra data follows name? */
if (namelen > 0) {
errno = EMSGSIZE;
return (-1);
}
return (0);
}
/* Compression pointer? */
if ((n & NS_CMPRSFLGS) != 0) {
errno = EISDIR;
return (-1);
}
/* Label too long? */
if (n > namelen) {
errno = EMSGSIZE;
return (-1);
}
/* Recurse to get rest of name done first. */
l = ns_name_map(nname + n, namelen - n, map, mapsize);
if (l < 0)
return (-1);
/* Too many labels? */
if (l >= mapsize) {
errno = ENAMETOOLONG;
return (-1);
}
/* We're on our way back up-stack, store current map data. */
map[l].base = nname;
map[l].len = n;
return (l + 1);
}
/* Count the labels in a domain name. Root counts, so COM. has two. This
* is to make the result comparable to the result of ns_name_map().
*/
int
ns_name_labels(ns_nname_ct nname, size_t namesiz) {
int ret = 0;
u_int n;
while (namesiz-- > 0 && (n = *nname++) != 0) {
if ((n & NS_CMPRSFLGS) != 0) {
errno = EISDIR;
return (-1);
}
if (n > namesiz) {
errno = EMSGSIZE;
return (-1);
}
nname += n;
namesiz -= n;
ret++;
}
return (ret + 1);
}
/* Private. */
/*%
* Thinking in noninternationalized USASCII (per the DNS spec),
* is this characted special ("in need of quoting") ?
*
* return:
*\li boolean.
*/
static int
special(int ch) {
switch (ch) {
case 0x22: /*%< '"' */
case 0x2E: /*%< '.' */
case 0x3B: /*%< ';' */
case 0x5C: /*%< '\\' */
case 0x28: /*%< '(' */
case 0x29: /*%< ')' */
/* Special modifiers in zone files. */
case 0x40: /*%< '@' */
case 0x24: /*%< '$' */
return (1);
default:
return (0);
}
}
/*%
* Thinking in noninternationalized USASCII (per the DNS spec),
* is this character visible and not a space when printed ?
*
* return:
*\li boolean.
*/
static int
printable(int ch) {
return (ch > 0x20 && ch < 0x7f);
}
/*%
* Thinking in noninternationalized USASCII (per the DNS spec),
* convert this character to lower case if it's upper case.
*/
static int
mklower(int ch) {
if (ch >= 0x41 && ch <= 0x5A)
return (ch + 0x20);
return (ch);
}
/*%
* Search for the counted-label name in an array of compressed names.
*
* return:
*\li offset from msg if found, or -1.
*
* notes:
*\li dnptrs is the pointer to the first name on the list,
*\li not the pointer to the start of the message.
*/
static int
dn_find(const u_char *domain, const u_char *msg,
const u_char * const *dnptrs,
const u_char * const *lastdnptr)
{
const u_char *dn, *cp, *sp;
const u_char * const *cpp;
u_int n;
for (cpp = dnptrs; cpp < lastdnptr; cpp++) {
sp = *cpp;
/*
* terminate search on:
* root label
* compression pointer
* unusable offset
*/
while (*sp != 0 && (*sp & NS_CMPRSFLGS) == 0 &&
(sp - msg) < 0x4000) {
dn = domain;
cp = sp;
while ((n = *cp++) != 0) {
/*
* check for indirection
*/
switch (n & NS_CMPRSFLGS) {
case 0: /*%< normal case, n == len */
n = labellen(cp - 1); /*%< XXX */
if (n != *dn++)
goto next;
for (; n > 0; n--)
if (mklower(*dn++) !=
mklower(*cp++))
goto next;
/* Is next root for both ? */
if (*dn == '\0' && *cp == '\0')
return (sp - msg);
if (*dn)
continue;
goto next;
case NS_CMPRSFLGS: /*%< indirection */
cp = msg + (((n & 0x3f) << 8) | *cp);
break;
default: /*%< illegal type */
errno = EMSGSIZE;
return (-1);
}
}
next: ;
sp += *sp + 1;
}
}
errno = ENOENT;
return (-1);
}
static int
decode_bitstring(const unsigned char **cpp, char *dn, const char *eom)
{
const unsigned char *cp = *cpp;
char *beg = dn, tc;
int b, blen, plen, i;
if ((blen = (*cp & 0xff)) == 0)
blen = 256;
plen = (blen + 3) / 4;
plen += sizeof("\\[x/]") + (blen > 99 ? 3 : (blen > 9) ? 2 : 1);
if (dn + plen >= eom)
return (-1);
cp++;
i = SPRINTF((dn, "\\[x"));
if (i < 0)
return (-1);
dn += i;
for (b = blen; b > 7; b -= 8, cp++) {
i = SPRINTF((dn, "%02x", *cp & 0xff));
if (i < 0)
return (-1);
dn += i;
}
if (b > 4) {
tc = *cp++;
i = SPRINTF((dn, "%02x", tc & (0xff << (8 - b))));
if (i < 0)
return (-1);
dn += i;
} else if (b > 0) {
tc = *cp++;
i = SPRINTF((dn, "%1x",
(((u_int32_t)tc >> 4) & 0x0f) & (0x0f << (4 - b))));
if (i < 0)
return (-1);
dn += i;
}
i = SPRINTF((dn, "/%d]", blen));
if (i < 0)
return (-1);
dn += i;
*cpp = cp;
return (dn - beg);
}
static int
encode_bitsring(const char **bp, const char *end, unsigned char **labelp,
unsigned char ** dst, unsigned const char *eom)
{
int afterslash = 0;
const char *cp = *bp;
unsigned char *tp;
char c;
const char *beg_blen;
char *end_blen = NULL;
int value = 0, count = 0, tbcount = 0, blen = 0;
beg_blen = end_blen = NULL;
/* a bitstring must contain at least 2 characters */
if (end - cp < 2)
return (EINVAL);
/* XXX: currently, only hex strings are supported */
if (*cp++ != 'x')
return (EINVAL);
if (!isxdigit((*cp) & 0xff)) /*%< reject '\[x/BLEN]' */
return (EINVAL);
for (tp = *dst + 1; cp < end && tp < eom; cp++) {
switch((c = *cp)) {
case ']': /*%< end of the bitstring */
if (afterslash) {
if (beg_blen == NULL)
return (EINVAL);
blen = (int)strtol(beg_blen, &end_blen, 10);
if (*end_blen != ']')
return (EINVAL);
}
if (count)
*tp++ = ((value << 4) & 0xff);
cp++; /*%< skip ']' */
goto done;
case '/':
afterslash = 1;
break;
default:
if (afterslash) {
if (!isdigit(c&0xff))
return (EINVAL);
if (beg_blen == NULL) {
if (c == '0') {
/* blen never begings with 0 */
return (EINVAL);
}
beg_blen = cp;
}
} else {
if (!isxdigit(c&0xff))
return (EINVAL);
value <<= 4;
value += digitvalue[(int)c];
count += 4;
tbcount += 4;
if (tbcount > 256)
return (EINVAL);
if (count == 8) {
*tp++ = value;
count = 0;
}
}
break;
}
}
done:
if (cp >= end || tp >= eom)
return (EMSGSIZE);
/*
* bit length validation:
* If a <length> is present, the number of digits in the <bit-data>
* MUST be just sufficient to contain the number of bits specified
* by the <length>. If there are insignificant bits in a final
* hexadecimal or octal digit, they MUST be zero.
* RFC2673, Section 3.2.
*/
if (blen > 0) {
int traillen;
if (((blen + 3) & ~3) != tbcount)
return (EINVAL);
traillen = tbcount - blen; /*%< between 0 and 3 */
if (((value << (8 - traillen)) & 0xff) != 0)
return (EINVAL);
}
else
blen = tbcount;
if (blen == 256)
blen = 0;
/* encode the type and the significant bit fields */
**labelp = DNS_LABELTYPE_BITSTRING;
**dst = blen;
*bp = cp;
*dst = tp;
return (0);
}
static int
labellen(const u_char *lp)
{
int bitlen;
u_char l = *lp;
if ((l & NS_CMPRSFLGS) == NS_CMPRSFLGS) {
/* should be avoided by the caller */
return (-1);
}
if ((l & NS_CMPRSFLGS) == NS_TYPE_ELT) {
if (l == DNS_LABELTYPE_BITSTRING) {
if ((bitlen = *(lp + 1)) == 0)
bitlen = 256;
return ((bitlen + 7 ) / 8 + 1);
}
return (-1); /*%< unknwon ELT */
}
return (l);
}
/*! \file */
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